The present invention relates to a unit for feeding an ordered succession of products to an unloading station.
The invention is advantageously used to feed products such as bars of soap, sweets and the like to a wrapping machine, to which the present specification refers but without thereby restricting the scope of the inventive concept.
Installations for the production and packaging of products of this kind usually include wrapping machines which must receive the products to be wrapped in ordered succession, that is to say, suitably spaced, and dispensing devices which feed products in a continuous stream. It is therefore necessary to space the products out during their transfer from the dispensing device to the wrapping machine.
In the art, feeding devices used to arrange products in ordered fashion for feeding to an automatic machine transport the products in succession on a first conveying device which moves in one direction at a first speed and which comprises a first, variable length conveyor portion extending from a loading station to a mobile transfer station. An ordered succession of the products are then transported on a second conveying device which moves at a second speed and which comprises a second conveyor portion of variable length to complement the first conveyor portion. The lengths of the two conveyor portions are varied by an adjusting device according to the position of the products moving on the first conveying device. Thanks to these devices, a continuous scrambled stream of products moving on the first conveyor can be arranged in way that makes the products suitable for subsequent handling.
If products are fed to the first conveyor not continuously but by feeding means that impart on the first conveyor a movement that is closely linked to the predetermined law of motion that governs the feeding means themselves, devices of the above mentioned type have proved to be unsuitable to arrange the products feeding out towards an unloading station and to correctly adjust their spacing as they are dispensed to the wrapping machine.
The aim of the present invention is to provide a unit for feeding the products to an automatic machine even when the products are fed to the first conveyor according to a law of motion imparted by respective feed means.
Accordingly, the present invention provides a unit for feeding an ordered succession of products to an unloading station, comprising an arranging device comprising a first and a second conveyor belt each constituting a first and a second portion of a feed path that has a defined total length and each portion being complementarily variable in length relative to the other, means for feeding the products to the first conveyor, a transfer station located between the two portions and comprising a carriage coupled to the two conveyors to complementarily vary the lengths of the two portions, transfer means mounted on the carriage and designed to transfer the products from the first to the second portion, wherein the feed means are cyclically mobile to transfer the products to the first conveyor in sets consisting of a predetermined number of products, the first conveyor and the transfer means being cyclically mobile according to a law of motion and timing dependent upon the cyclic motion of the feed means.